Democrats severely underestimated the seriousness of legal arguments against President Barack Obama’s sweeping healthcare law, Grace-Marie Turner, the head of the Galen Institute tells Newsmax.TV.

The thorough grilling that Supreme Court justices gave lawyers on both sides of the case this week proves that experts who predicted the law would sail past challenges to its constitutionality, were mistaken, she added.

“After this week’s arguments, they have to realize they did seriously overstep the bounds in declaring that the individual mandate was something that was within the powers of Congress,” said Turner, who founded the public policy research organization in 1995 to push free-market ideas in health policy.

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“Many of us have been saying … that that’s one step too far, that there is no power in the Constitution to tell us how we have to spend our after-tax money.”

The Galen Institute was party to an amicus brief before the court supporting the Atlanta-based 11th Circuit Court of Appeals decision that the Affordable Care Act – also known as “Obamacare” – is unconstitutional.

Turner is hopeful that the Supreme Court will overturn the individual mandate part of the act and then decide that the rest of the law has to fall along with it, but she said the questions from the justices – which observers say pointed toward a government defeat – were not conclusive.

And she admitted it is difficult to get inside the minds of the six men and three women who hold the whole future of the nation’s healthcare policy in their hands, but she was impressed with the tough, combative questions they asked the attorneys. “I’m really uncomfortable calling this,” she said.

“All I know is that the argument was very well done. They asked really, really shrewd, smart questions and they are going to do the absolute best job they can in deciding.”

Turner did not agree with CNN legal analyst Jeffrey Toobin, who said the government’s case was a “trainwreck.”

“The questions were very subtle. Who knows what is going to be the fulcrum point in Justice [Anthony] Kennedy’s decision?” she asked. “He seems very concerned about the question of uncompensated care.

“Is healthcare different? Does the fact that we never know whether or not we are going to need healthcare mean that the federal government can require you to purchase health insurance or otherwise you are going to shift those costs on to someone else? He seems really, really concerned about that and if he is concerned enough, he may decide to uphold the individual mandate.”

But she agreed with former Florida attorney general Bill McCollum, who told Newsmax on Tuesday that Chief Justice John Roberts could be the key vote. She said that he normally votes last and could make a tactical decision that he does not want a 5-4 decision and go with the more liberal justices, if Kennedy also joins them.

“He will know whether or not Justice Kennedy has decided ‘No, I just can’t do it, I can’t strike down the law.’ Then it’s possible that Justice Robert might go along so that it’s not a 5-4 decision.